River Conditions

Having enough flowing water is essential for river health. We can keep track of Ipswich River flow levels by monitoring two USGS graphs that show flows measured at two real-time streamflow gauges on the Ipswich River, near the South Middleton and Willowdale Dams (Hamilton/Ipswich). This is a good way to assess whether flows are above or below ecological protection levels (is there enough water for fish and other aquatic organisms?) and whether there is enough water to paddle certain stretches of river that are flow dependent.

Real-Time Data:

Ipswich River Near Boston St., South Middleton

Based on USGS study, summer flow rates at or above 19 cfs at the South Middleton gauge can be considered ecologically safe. Flows above this level are generally suitable for navigating the main stem of the river through North Reading.

Ipswich River Near Willowdale Dam, Ipswich

Based on a USGS study, summer flow rates at or above 53 cfs at this gauge can be considered ecologically safe. Flows above this level are generally suitable for navigating the main stem of the river from Winthrop St. in Ipswich to the Ipswich River Watershed Association’s Riverbend headquarters in Ipswich.

LOW FLOWS EXPLAINED:
Low flows are linked to the loss of river dependent fish such as brook trout and it can make shallow stretches difficult for paddling. Low flows dry up critical habitat for fish and other aquatic organisms, cause water temperatures to rise and lower dissolved oxygen levels.

The ecological protection flow level at the South Middleton gauge, maintained by the U.S. Geological Survey (USGS), is 19 cubic feet per second (cfs) while at the Ipswich gauge location, it is 53 cfs. These levels were determined in a USGS study to be a safe threshold for fish and other aquatic organisms. During 2013, flows fell below these levels from mid-August until the end of November. These long periods of low flows occur annually and have a long-term impact on the ability of the river to support a diverse community of organisms.

Conditions at Martin’s Brook in North Reading this fall were so dry that the stream bed was now being used by ATV’s. Martin’s Brook is especially hard hit from water withdrawals from North Reading and Wilmington town wells. These wells collectively withdraw over 2 million gallons a day from the Martin’s Brook aquifer, which normally would sustain the Brook’s flow during dry periods. Photo: S. Sullivan

Read more about recent changes to the state’s water withdrawal regulations, the long-awaited final regulations as a result of Sustainable Water Management Initiative (SWMI) and how they negatively affect our watershed.

WATER QUALITY:

When flows are low, water temperatures rise more rapidly and dissolved oxygen levels decline. Prolonged low flows can lead to fish kills and loss of diversity among aquatic insects. Most fish require dissolved oxygen levels of 5 parts per million (ppm) or greater. Our volunteer water quality monitors consistently observe dissolved oxygen levels below this level during the summer when flows are lowest. Our macroinvertebrate sampling has recorded a high proportion of organisms that can tolerate low water quality and fewer sensitive organisms than would be expected for a healthy river.

Low dissolved oxygen levels are a serious threat to the survival of fish and other aquatic organisms. In the summer, the upper watershed experiences the most severe impact from water withdrawals and higher amounts of surface runoff during storms. Click image to enlarge

Benthic macroinvertebrates (bugs) are good indicators of river health. Mayflies, which are sensitive to poor water quality, should be present in a healthy river system, but are not common in the Ipswich River. Instead, amphipod crustaceans or scuds (listed as OTHER) are very common and are highly tolerant of poor water quality. Click image to enlarge.

We can all do our part to conserve water, improve flows and restore more natural conditions and biodiversity to the Ipswich River. Do you know where your water comes from? Learn more about your town’s drinking water sources.

Please explore our save water, save money page for more tips and information on saving water indoors and outdoors.

WATER QUALITY MONITORING

Our volunteer RiverWatch monitoring program assesses the health of the Ipswich River. Volunteers collect data monthly from March-December on weather conditions, rain in the last 48 hours, water color, odor and clarity, water temperature, dissolved oxygen, velocity, depth and conductivity. Measurements are taken at 32 sites throughout the watershed. Monitoring reports are available here.